Automatic drain valve



n 3,1935l M YPKuDl- LA 2,022,724

AUTOMATIC DRAIN VALVE Filed March 14', 1934 I' 47 ia" A lsgullll ff if ff \7, f4

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I Patented Dec. y 3, 1935 UNITED STATES Parli-lar oFFicE I An'romrzinzim VALVE Milton P. Kudolla, Chisiil: 715 428 A Q ons claim.' I ,(ci. 1211-103) y I A My invention relates to autmatic drain valves and has Afor an object the provision of -a `valve which may be placed at the base-,of a compressed air tank and employed vto permit escape of water of condensation from the tank and from the valve without the intervention-of an operator. Ig` am aware that generally speaking such devices have been heretofore provided and one of such devices is disclosed in my Patent No. 1,907,299, which issued on an application illed byme on March 2l, 1932, given Serial No. 600,356, and entitled, Automatic drain devices".

- somedimouities have arisen in connection with I the use and operation of prior art devices of this character, and an object of the present invention is to eliminate these difficulties. f

Some of these diiiiculties have been the necessity of employing a particular type of spring for each particular installation in which the maximum and minimum of air pressure in the compression tank have been varied. For instance, a

tank having a maximum pressureof one hundred pounds and a minimum pressure o; eighty-:dve b ase.

quires that a plurality of accuratelymade and expensive springs bekept in stock for assembly with the valves which' are to be employed with the different tanks. I'he present invention entirely ,eliminates this diiculty and the valve may be employed on any tank adapted for any maximumpressure or any pressure within very broad limits. Another` difficulty heretofore experienced has been due to the provision of very complicated mechanism and subsequent failure of some working parts.v Other objects of my invention are economy of construction, simplicity of construction, and perfection of operation. Because of .thesefeatures seldom neededrepairs may be made easily and quickly and any needed grinding of the valves maybe accomplished very easily. l x

Other objects will appear hereinafter.

My invention may be best understood by reference to the accompanying drawing, .in which.:

Fig. 1 is a side elevational view oi my device in the position in which it is found in the 'ordinary installation on a compressed air tank;

Fig. 2 is a sectional view taken substantially 1 on the line 2--2 of Fig. 1;

Fig. 3 is a sectional'vview taken substantially I Fig. 4 is a sectional view taken substantially 4on thelin'e 4-4 of Fig. 3;

Fig. 5 is a'sectional view taken substantially on the line 5-5 of Fig. 2; and

Fig. 6 is a detail view in section of a modified 3 form of spring which may. beemployed in place o f the ordinary coil spring in the lower part of my device. l

portion of bore I4 is internally threaded as at I6 to receive a locking plug I'I having longitudinally 15 extendingslots I8 for the admission of water of condensation from the compressed (not shown on the drawing but well-known in the art and shown in my issued-patent heretofore mentioned). Beneath the plug I1 straining ma- 20 terial I9 is placed for removing `any solid substances from the water of condensation, and a screen 28 supports straining material I8l at its The opposite end of cylindrical housing II) is 25 externally threaded as at 2| and is open at the oppositeendalso. Thus a longitudinally extending cylinder 221s provided Within the housing and is in communication with the restricted bore Il. Likewise the diametrical dimensions of cylindri- 30 cal bore 22 are uniform throughout the length of said bore. A packing gasket 28 in the form of a ring may be placed on the annular end of housing I0. and an Vinternally threaded screw cap 24 having a wrench engaging stud 25 may be screwed onto the threaded end 2l in order to close the end of the cylinder. o Y AA longitudinally slidable lpiston structure is provided within cylinder 22 by a circular disc 2s and other parte later to be described. The 4.0 disc 26 is of suflcient diametrical dimension to provide a close sliding fit with the wall of cylin- `der 22, and an upper packing leather cup 2'II`` 2l a retaining disc 29 is placed in axial alignment with packing cup 2l, disc 28, and cup 28.

In the open end of packing leather cup 28 a similar disc 3,8 is arranged in a similar manner so thatthepacking leather cups and the disc f /ceive anchoring screws 4|. In the base of brack 26 are pressed between discs 29 and 30. `It is of course understood that the packing leather cups 21 and 29 are of sufficient diametrical dimension to effect an air-tight sliding connection with the wall of cylinder 22.

Disc 26, packing leather cups 21 and23, and discs 29 and 30 are provided with annular axial apertures through which a clamping bolt 3| is adapted to extend. The bolt 3| is also formed with an enlarged abutting shoulder 32 and an elongated head 33. An axial cylindrical bore 34 extends from the upper end'of bolt 3|`to a valve seat later to be described and thus affords a communicating passage between the portion of the cylinder 22 above the disc 26 and the portion of the cylinder which is below the disc 26. The upper end of clamping bolt 3| is externally threaded to engage the internal threads of `a clamping nut 35.

The lower enlarged end 33 of. clamping bolt 3| carries an enlarged axial bore 36 which is connected by a conical valve seat with bore 34 heretofore mentioned. Within the bore 36 is arranged a valve member 31 having a conical valve head 38 which of course cooperates with the conical valve seat heretofore mentioned in closing the bore 34 from communication with the bore 36. The valve member 31 is somewhat triangular shaped in cross-section as can be seen in Fig. 4, andthe apexes thereof are adapted to slide along the interior cylindrical walls of bore 36 and provide a guide for the valve head 36. k

Referring now to Fig. 3 a substantially U- shaped bracket 39 may carry laterally extending attaching lugs 4|) having appropriate bolt hole openings, and the disc may be tapped and ythreaded at diametrically opposite points to reet 39 and in axial alignment ywith bore 34 the conical valve seat-communicating with bore 34 and also in axial alignment with bore 36 is arranged an annular aperture through which a bolt 42 is adapted to extend. The bolt 42 carries in the upper face oi its disc-like head a dished spring seat recess 43 for the reception of a coil spring 44 whose opposite end is incased in a bore 45 in the lower "end of valve member 31. The lower end of bolt 42 extends through the aperture in the base of bracket member 39 and is threaded to engage the internal threads in the body of a valve member 46. The cap 24 heretofore mentioned carries an enlarged axial bore in which a plug 41 is arranged, and a valve seat 49 is carried in the upper face of plug 41. `The valve V46 just mentioned cooperates with the Valve seat 48 in closing the bore in plug 41.

,The lower end of plug 41 is open and communicates with a bore 49 which is arranged axially of the cap 24 and extends through wrench engaging stud 25. The bore 49 thus communicates with the atmosphere and when the valve 46 is open water of condensation is permitted to drain from the lower part of cylinder 22. A coil spring 55 is preferably interposed between the lower face of bracket 39 and the upper inner face of cap 24 and also `arranged around the upper end of plug 41 so as to be kept in proper alignment by the protruding end of sfd plug 41. The main body of valve 46 is preferably of a somewhat triangular shape as is valve member 31 so that the -apexes on the lateral faces will serve as guides for the valve and yet there will be sulcient space for the escape of liquid past the valve when it l is open.

A modiiled form or spring may be substituted amava: l

in place of spring 50 and may be seen at 5| in Fig. 6.

An aperture 52 is arranged intermediate the ends of the leaf spring 5| and receives the end of bolt 42 therethrough. The function of leaf springV 5| is similar to that of 5 spring 50.

From the foregoing description it canbe seen that there are two chambers provided within the cylindrical housing I0, namely, the upper inlet chamber 53 and the lower outlet chamber 54, and 10 the, valve 31 periodically opens and closes a communicating passage between these chambers.

In operation my drain valve is employed at the base of an air compressor tank adapted for a certain maximum pressure and a certain minii5 mum pressure. For example, if the air compressor tank is adapted for one hundred pounds maximum pressure and a minimum pressure of eighty-five pounds, it can be seen that when the maximum pressure iswin the tank the piston-like 20 member separating chambers 53 and 54 will be forced downwardly from a position shown in Fig. 2. When piston member reaches the limit of its downward travel the lower face of bracket 39 will be impinging upon the upper face of valve 46 25 in order to cause the closing of said valve. At substantially the same moment the high pressure in chamber 53 will cause the unseating and consequent opening of valve 31 and since th'e coil spring 44 is preferably madevso as to resist a 30 pressure of a-few pounds, such as ve pounds pressure, the pressure in the lower chamber 54 will be built up until there is no longer a sutilcient differential between the pressures of chambers 53 and 54 to maintain the valve 31 in an'35 open position. At this time the valve 4will be closed by the spring pressure of the said spring 44, and this condition will remain until the pressure in the compressor tank is materially re` duced. During the period of time while the valve head 38 is out of contact with its seat any water of condensation in the upper chamber 53 may drain into the lower chamber 54. When the pressure in -the compressor tank is reduced to a pressure of ninety pounds for example the pressure in the lower chamber 54 will of course be greater than ninety pounds, depending upon'the strength of spring 44. If however the spring 44 is adapted to resist a pressure of ve pounds the pressure in the lower chamber should be about ninety-five pounds. The greater pressure beneath the piston member will of course force it upwardly and carry with it bracket member 39. When this happens the base of bracket member- 39 will exert an upper force on the head of bolt 55 42 and carry upwardly the valve 46. The water of condensation in the lower chamber 54 will then be free to pass out of the valve through outlet bore 49. Of course when the valve 46 is opened the air pressure in outlet chamber 54 is reduced 60 quent drain period follows through the same procedure as outlined above. This opening and closing action continues intermittently during use vof the compressor tank so that it is kept lpractically dry of condensed moisture. The

spring 53. is adapted to resist a pressure of about five pounds preferably, and in actual test the valve 46 closes when the air pressure in outlet 75 chamber falls -aboutrve poundsA below the pressure of the inlet chamber 53.

The spring' A5|! oi' the -modified .form 5i will vassist in raising the bracket and piston member during the drain time; thks-spring'also acts as a cushion for the bracket 39 when air pressure is suddenly increased within the compressor tank and hence likewise increased in chamber 53.

All the parts of the'device are'readily accessible o for any necessary adjustment or repair when the piston member dividing said cylinder into an inlet'chamber Iand an outlet chamber, an inlet passage adapted to communicate betweenA ysaid inlet chamber and the interior ofa compressor tank, an intercommunicating passage connecting said inlet chamber and said outlet chamber, an outlet passage communicating between said outlet chamber` and the atmosphere, and means for-` maintaining said intercommunicating passagein a closed condition and opening said outlet passage when the air pressure in said inlet chamber falls below the air pressure in 'said outlet chamberto any considerable extent. y

2. A device .of the character described com-- prising a housingl having a cylinder therein, a piston memberseparating the cylinder into an inlet chamber and an outlet chamber, an intake passage adapted to communicate between the intake chamber and a compressed air tank, a com-,- municating passage between said inlet chamber and said outlet chamber, a valve for closing said last mentioned passage, an outlet passage from said outlet chamber communicating with the atmosphcre, an outlet valve for closing said outlet passage. means connected to said piston member and the outlet valve and: adapted lto actuate the outlet valve to close the outlet passage when said piston is moved in one direction and to open said passage when. said piston is moved in the opposite direction, and a. spring member supported by said means for urging the ilrst s aid valve for closing saidf communicating passage between said inlet 'chamber and saidoutlet chamber inteclosed -position.=

3. A device of the character described compricing a housing having a cylinder therein, a. piston member dividing said cylinder into an' inlet chamber and an outlet chamber, a passage connecting said inlet chamber with theinterior of a compressor tanken intercommunicating passage extending Abetween said inlet chamber andisaid outlet an outlet passage communicat- 3 ing between said outlet chamber and the atmosphere, a spring urged valve for closing said intercommunicating passage, a lvalve for closing said outlet passage, and means connected tosaid piston member for opening and closing said last mentioned valve. said means also being adapted to serve as a spring support for said spring urged intercommnieating passage valve,

4. A deviceoi" the character described comprising a housing having-a cylinder therein, a piston member dividing said cylinder into an inlet chamber and an outlet chamber, a passage con'- necting'said inlet chamber with the interior of a compressor tank, an'intercommunicating passage extending between said inlet chamber and said 1 outlet chamber, an outlet passage communicating between said outlet chamber and the atmos phere, av spring urged valve for closing said intercommunicating passage, a valve for closing said outlet passage, and a Q -shaped bracket member l secured tothe outlet face of said piston member and adapted to serve as a spring support for said spring urgedvalve and being adapted to open and close said outlet v alve as said piston member is moved in said cylinder.

5. A 4device of the character described comprising a housing having a cylinder therein. a piston member dividing said cylinder into an inlet chamber and an outlet chamber, an inlet passage adapted to communicate between said inlet chamber and .the interior of a compressor tank. an intercommunicating passage connecting said Ainlet chamber and said outlet chamber, an outlet passage communicating between said outlet chamber and the atmosphere, and means `for maintaining said intercommunicating passage in a closed 'condition and opening said outlet passage when the air pressure'in said inlet chamber falls below the. air pressure in said outlet chamber to any considerable extent, said means also 40 being adapted to close said -outlet passage when .the airpressure in the outlet chamber falls below the airpressure in the inlet chamber to any considerable extent.

SQA device of the character described comprlsing a housing having a cylinder therein, a

piston member dividing said cylinder into an inlet chamber and an outlet chamber, an inlet passage adapted to communicate between' said inlet chamber and the interior oi'A a compressor tank, 50 an intercommunicatingpassage connecting said a inlet Achamber andsaid outlet chamber, an outlet passage communicating between said outlet chamber and the atmosphere, valves controlling 1 said intercommunicating passage and said outlet 55 passage respectively, and means for maintaining the valve controlling said intercommunicating passage in a closed condition and opening the valve controlling said outlet passage when the air pressurev in saidv inlet chamber falls below the-G0 air pressure in said outlet chamber to any con#- siderable extent.

i MIN P. n'liifiil, 

